🛡️ Debate Believers or skeptics

There is, you engaged in two fallacies here, clumsilly avoiding addressing the first fallacy I called you out on with another (straw man).

Anyone can note that you still failed to address the post.
 
If you know (as you claim) what a straw man argument is, then please point out how a reductio ad absurdum argument equates to a straw man.
Personally, I don't think you know what either type of argument is, even though I explained one of them thoroughly.

Or, will you say the Inuit were in South Florida?

Harte
 
Also, you never addressed the point I asked about, so saying I didn't address something (even though I did) is hypocritical of you.

To wit - If absence of evidence is not evidence of absence, then what, exactly, IS evidence of absence?

Harte
 
Dude, let's go back to the post you ignored by posting some straw man nonsense instead of addressing what was actually argued..


The idea only works when you exhaust all possible events. For instance, if I have a bucket of blue marbles, and suspect you placed a red marble in the bucket, then after having examined all the marbles and finding no red marbles, I can conclude the original hypothesis to be false because I exhaustively searched the bucket and found no red marbles. But if for some reason I could not access all the marbles; for instance, only being able to sample 10% of the marbles in the bucket; the fact that I found no red marbles does not disprove the hypothesis that you placed a red marble in the bucket.


At one time, there were marine biologists who said there were no such thing as giant squid because none of them ever observed any. Until somebody did and recorded it. At one time astronomers declared that rocks could not possibly fall from space, contradicting what rural folk had been telling them all along. Then they observed rocks falling from space.

The fallacy lies in your assumption that you exhausted your observations. You don't know that because you can't make assumptions about what you have not observed. You especially cannot make assumptions about the breadth and depth of phenomena you have not observed.
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I would add that, in this bucket experiment, as I approach the total number of marbles examined, my confidence in a conclusion can grow stronger. If there were a thousand marbles, and I was able to examine 900 marbles without finding any red marble, then my confidence that the hypothesis was false grows, converging on 100% as I examine the last marble, finding no red marble.

But in practical matters, and this is where the fallacy really fails terribly most of the time, you have no idea how many "marbles" are in the bucket corresponding to some problem. The only thing you really know is that you don't know. So to say you examined 900 marbles and therefore your confidence level that some event or phenomenon does not exist reaches 90-95% is utterly absurd because you have no idea the scope of possible events or observations.

Thus, to say absence of evidence is evidence of absence, when you have no idea how broad some phenomenon may be, or how limited your ability to measure it may be, or any number of limiting factors, is quite simply foolish. Fools throughout all time do this. This is how hedge fund traders make fortunes, turning fools upside down and cleaning out their pockets every time some high impact event occurs that prior probability said was nearly impossible (until it wasn't).

Just limit yourself to what you actually know. It's fine to speculate. It's fine, even, to state openly that you don't believe something exists (and even give reasons why). But going about declaring something you don't understand as nonexistent because you were not personally shown evidence of it is the act of a fool. Don't be that guy. History is replete with examples of fools in academia making such statements only to be proven wrong.
 
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Looks like you are confused about the difference between evidence and proof.

The quote does NOT say "absence of evidence is not proof of absence."
If it did, that would be true. But the quote as stated is just ignorant, which is the point Sagan was making when he coined it.
I already made that point in this very thread:
Harte said:
You are mixing "evidence" with "proof" here.
Evidence that a thing happened doesn't mean that thing actually happened. That would require proof.

You are also incorrect when you quote Sagan's sarcastic "absence of evidence" statement.
Unless you believe that there can be no such thing as absence of evidence.

That is, if absence of evidence does not constitute evidence of absence, then what exactly would constitute evidence of absence?


I certainly believe this concerning members of online internet forums. These are the only people I've seen use the idea that "Scientist think we know everything" as a straw man to prop up their arguments.

Any thinking person already knows that we don't know everything.
As a trivial example, if everything was known there would be no more scientists, just engineers.

Harte
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Maybe you are responding to my posts without reading them.
Now, you have accused me of using a straw man, and I asked you to point it out. I take it then that you can't?

Harte
 
@Harte , the distinction between evidence and proof you are noting is accurate. The caveat is that unless you are omniscient, evidence of absence is only possible once the limits of context are recognized. If I've done a thorough search of a park and have found only white swans, then I could say I have evidence of there being no black swans during my search, in the park. The evidence, however - and this is a subtlety - is not the presence of white swans but in the thoroughness of my search and not locating any black ones. White swans, whatever their number, cannot constitute evidence of anything except the existence of white swans, which is easily recognized as soon a black swan enters the park, as at that point we could hardly insist that white swans constitute evidence to the contrary. And although we may feel confident having scoured the park and finding only white swans in saying "Today I thoroughly searched the park and found no black swans and that for me is evidence that there are no black swans in the park", we should recognize that the search provided no evidence about the status of black swans in the park on the previous days nor in the future nor in the world outside the scope of the search. We can have levels of confidence in what to expect in our day to day life because our experience is local and generally there are not radical changes in most things we experience in our proximity. But the common sense that allows us to navigate the world with working hypotheses on what to expect moment to moment does a disservice if applied to support claims of the universality of our local expectations.
 
Harte said:
Looks like you are confused about the difference between evidence and proof.

The quote does NOT say "absence of evidence is not proof of absence."
If it did, that would be true. But the quote as stated is just ignorant, which is the point Sagan was making when he coined it.
I already made that point in this very thread:

Maybe you are responding to my posts without reading them.
Now, you have accused me of using a straw man, and I asked you to point it out. I take it then that you can't?

Harte
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I am confused about nothing here. You still failed to respond to anything I posted.

And I know it's not me, since Sonix just grasped it, so it's your problem.
 
Sonix said:
@Harte , the distinction between evidence and proof you are noting is accurate. The caveat is that unless you are omniscient, evidence of absence is only possible once the limits of context are recognized. If I've done a thorough search of a park and have found only white swans, then I could say I have evidence of there being no black swans during my search, in the park. The evidence, however - and this is a subtlety - is not the presence of white swans but in the thoroughness of my search and not locating any black ones. White swans, whatever their number, cannot constitute evidence of anything except the existence of white swans, which is easily recognized as soon a black swan enters the park, as at that point we could hardly insist that white swans constitute evidence to the contrary. And although we may feel confident having scoured the park and finding only white swans in saying "Today I thoroughly searched the park and found no black swans and that for me is evidence that there are no black swans in the park", we should recognize that the search provided no evidence about the status of black swans in the park on the previous days nor in the future nor in the world outside the scope of the search. We can have levels of confidence in what to expect in our day to day life because our experience is local and generally there are not radical changes in most things we experience in our proximity. But the common sense that allows us to navigate the world with working hypotheses on what to expect moment to moment does a disservice if applied to support claims of the universality of our local expectations.
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Yet you still have an absence of evidence for the black swans, which constitutes evidence of the black swan's absence from the park.
Obviously, it is not PROOF that there are no black swans in the park. One may have been following 50 meters behind you during your search.
Thus the difference between "evidence" and "proof."
So, you can't point out the straw man you claimed I used?

Now, will you answer the question, or continue to dodge?
If absence of evidence is not evidence of absence, exactly what would be evidence of absence?
Because that's the only evidence of absence there is. And if that's NOT evidence of absence, then there can be no evidence of absence and we are left with the assumption that every imaginable thing is worth looking into, even though we've never seen any evidence for those things.


Harte
 
Kairos said:
I am confused about nothing here. You still failed to respond to anything I posted.

And I know it's not me, since Sonix just grasped it, so it's your problem.
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You have failed to respond to MY posts. Except to claim I used straw men, which you seemingly can't point out.
Here is what led me to point out that you don't seem to discriminate between evidence and proof:
Thus, to say absence of evidence is evidence of absence, when you have no idea how broad some phenomenon may be, or how limited your ability to measure it may be, or any number of limiting factors, is quite simply foolish.
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Even a small survey of your marbles is certainly evidence of absence of red marbles. It is not to say that there are no red marbles in the bucket. It is to say that there is no evidence of red marbles in the bucket.

And finding a red marble (after a more thorough search) would not be evidence of a red marble in the bucket, it would be PROOF of a red marble in the bucket.

See, evidence and proof are separate ideas.

Harte
 

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